robotpy-cscore is not currently able to use the opencv-python package on pypi, you will need to install python bindings for OpenCV some other way.

USB Camera Support

The cscore library currently only supports USB cameras on Linux. On other platforms you will want to use OpenCV to open a VideoCamera object. You can check at runtime to see if cscore is compiled with USB camera support by checking for the presence of a ‘UsbCamera’ class. If it’s not there, it’s not supported.

See the example for using OpenCV in this manner.